1. Field of the Invention
This invention relates to a data entry system for digital computers, and more particularly to such a system which employs an expert software system to facilitate the generation of electronic data forms with complex interrelationships between fields and subforms and in which the validity of entries is assured as the data is entered.
2. Background Information
Many data entry systems for digital computers utilize a form format in which background text and blanks or fields in which the user is to insert data are presented on a display screen. The user proceeds from field to field supplying the requested data. In some instances, the user is presented with a list of entries for a particular field in the form of a menu from which the user can select an entry. This eliminates the need to remember suitable entries for that field and to type in the selected entry, thus saving time and reducing errors. Where there is much data to be entered, successive forms can be presented to the user. The succession of forms presented cannot depend on entries made in particular fields, and thus, the path through a network or hierarchy of forms cannot vary depending upon selections made by the user at a given field always the same.
While such data entry systems aid a user in inputting data into a digital computer, particularly by reducing typing requirements and speeding up data entry, in all but very small, and therefore limited applications, they do not assure that the data will be valid and consistent when it is entered. Expert systems are examples of computer programs which frequently use the form format of data entry. It is widely acknowledged that user acceptance is the key to the success of an expert system. A large percentage of expert systems employ a user interface of the kind that the MYCIN system (Stanford University, circa 1975) used. As this type of system processes rules, it decides what further questions need to be asked of the user. The question is printed on the screen and the user is prompted to type in some information in a "fill in the blank" format. Users are often frustrated by this approach, especially novice users, because the system may ask questions in a seemingly random fashion. It is possible not to understand what is really being asked. It is also possible not to know what the legal answers to a question are, and it is further possible to enter a value which the system discovers is invalid only at a later stage.
Many other expert systems use an interface like the one employed by DEC's R1 system (circa 1980). R1 requires all answers to all questions to be typed in up front, before the expert system begins processing rules. This method has the advantage that all the questions are answered at the same time, but has the disadvantages that questions irrelevant to a specific job must also be answered, and that the user still may not know what the legal answers to a question are. In addition, the expert system only detects inconsistent or invalid responses after all of the input has been gathered and rule processing has commenced.
There remains a need for an improved system for inputting data to a program running on a digital computer.
More particularly, there is a need for such an improved system for inputting data to a program in a form format.
There is a further need for such a system for inputting data to a program in which the data is verified as it is entered.
There is a particular need for such an improved system for inputting data to an expert system.
There is also a need for such an improved system for inputting data to a program running on any digital computer and in particular a personal computer.